Flame cultivation of plants



' Oct. 15, 1946. P. c. M LEMORE ,FLAIE CULTIVATION OF PLANTS Original Filed May 8. 1942 4 Sheets-Sheet 1 RN QQ Oct. 15, 1946.

FIG. MCLEMORE FLAME. CULTIVATION OF PLANTS ri inal Filed May 8. 1942 4 Sheets-Sheet 2 E. 7 v ,3 t MN .1 MAR M m M z f .W I n C iv W 1 fi i Q m Z asix .3 b a T w r 0% M a 7 1 mm n w m /u U ,k WV A W mm. mm, u H. .N 1, ii s i f 3, Nfil m9 IQ mm N as M w A m 3% m9 Q Wm \m %& Nw 1 I m, \R. Q H mm NM NM RS Q% a. Q \w & w R s m nm E E n SW 1 mm 9Q M N1 mfi k N \\l1|\|1li I1 I i mi Q MN 0d. 15, 1946. p, c McLEMORE Re 22,803

FLAME CULTIVATION OF PLANTS Original Fiied lay a. 1942 4 Sheets-Sheet s jrzuerzz'fvr:

P. c. M LEMORE Re 22,803

FLAME CULTIVATIQN 0F PLANTS Original Filed l lay a, 1942 4 Sheets-Sheet 4 rzuerzior:

Reissued a. 15, 1946 UNITED STATES PATENT OFFICE Serial No. 442,206, MI! 8, 1942.

Application for reissue February 11, 1946, Serial No. 646,729

47 Claims.

The present invention relates to the flame cultivation of plants. The disclosure of this application embodies improvements upon the disclosures of my prior Patent No. 2,327,204, issued August 17, 1943, and my prior application Serial No. 364,140, filed November 4, 1940.

My improved flame cultivation appears to have its principal field of utility in the cultivation of cotton plants, but the invention is also applicable to the cultivation of other crops, such as corn, legumes, potatoes, tomatoes, sugar cane, ramie, and even to crops such as beets, pineapples, etc. It may be applied to the cultivation of annual plants or perennial plants, and even to such types as bushes and trees if desired, particularly when it concerns the problem of suppressing volunteer vegetation such as weeds of casual or incidental plants, as against those intended to constitute the crop or to furnish the crop. Furthermore, while the apparatus herein disclosed is particularly applicable to the cultivation of row crops, the invention in its broader aspect is not limited to row crops, as will be apparent hereinafter.

In my aforementioned prior applications, I have disclosed an improved method 'of and apceeds on the discovery that there is a marked difference in the resistivity of plants to the application of heat, particularly heat at high temperature. I have found that by the application of heat under suitable control as to time, temperature, volume, and point or region of application, certain of the varieties in a stand of vegetation of mixed character may be selectively destroyed. The useful application of the principle involved in my invention resides not so much in the natural resistance to hotter or colder climates of different kinds of plants or vegetation, but rather in the different effect of, or reac' tion to, suddenly or rapidly applied heat, particularly at high temperatures; that is, applied at a high temperature differential. Such a process is comparable to singeing. The shape of a blade of grass is such that it presents a large area for a given volume, and also, each point in its cross section is at only a minimum distance from the surface. Hence when a flame is applied to both grass blades and to a stemmed crop plant, the grass may be cooked,- scorched or burned before the stemmed crop plant receives substantial injury. This results largely from the shape of the subject treated. Rapidly applied heat, that is, a high temperature gradient, will also selectively act as between a smaller plant and a larger plant of the same species.

, 2 v The apparatus of the present application comprises a vehicle adapted to travel along the rows of the crop plants and carrying liquid fuel burnersv from which flames are projected adjacent to or around the bases 'of the crop plants. Flames mayalso be projected along the middle areas between plant rows. For the cultivation of crops such as cotton, corn, etc., the cultivating vehicle is preferably a high wheeled tractor of the cmtivator type capable of straddling two plant rows.

However, for the cultivation of trees, orchards, high bushes, etc., it will be apparent that various other types of tractors or vehicles may be employed.

1:: One of the features of the present application resides in the employment of improved burners of the high pressure atomizing type for projecting the cultivating flames. The hydrocarbon fuel is fed to each burner under pressure and is projected therefrom in the form of a high pressure jet. A source of compressed air is also fed to each burner and is projected therefrom in atomizing relation to the jet of fuel. The fuel can be distillate, furnace oil, or any one of a wide range of fuel oils capable of being atomized and burned paratus for the cultivation of plants which proin the above manner. The high pressure atomizing type of burner is particularly advantageous in effecting flame cultivation of plants because it enables practically any desired length and so. shape of flame to be obtained, and because it also enables the intensity or temperature of the flame to be' adjusted through a relatively wide range. In many instances it may be desirable to employ a relatively long flame for reachingin under long overhanging leaves or branches of the crop plant so as to cause the flame to impinge against the ground all around the base of the plant without injuriously searing these overhanging leaves or branches of the plant. Furthermore, it may be 40 desirable to make the flame of fan shape or fish-- tail shape characterized by a wide horizontal span or dimension capable of covering a considerable area of ground, and a relatively short vertical dimension so as to minimize the likelihood of iniuriously burning the upper leaves or foliage of the plant. These attributes oflong length of flame and flat shape of flame are readily obtainable in my improved structure by the use of high pressure atomizing burners and by the use of particular shapes of burner nozzles, as I shall presently describe.

The pressure type of atomizing burner also enables the intensity or temperature of the flame to be adjusted over a relatively wide range. There are a wide variety of conditions when the ability to adjust the o e flame over'a substantial range is quiteimportant. For example,

.when starting flame cultivation ofsmall plants or young plants which have Just broken ground it may be desirable to havethe burner flames of relatively low intensity; Conversely, when the plants are more advanced and have larger thicker stalks capable of standing higher temperatures it may be desirable togreatly increase the in-' tensity of the burner flames. The nature of the tivator by varying the pressure maintained inv the fuel oil reservoir, by varying the pressure in the compressed air reservoir and possibly by controlling the valved flow to the burners. The apparatus of my invention includes an air compressor'mounted on the tractor and driven from a power take-oil! of the tractor, this compressor maintaining a relatively high pressure on the fuel oil in the fuel reservoir, and also maintaining a relatively high pressure in the compressed air chamber. As illustrative of very successful if operating conditions, I flnd that a pressure of approximately 40 lbs. on the fuel and the presaaeca weeds, grass or other parasitic vegetation may A typicalfweevil infested cotton fleld will have boll weevils in all stages of development, such as the punctured or egg infested squares of the plant, the larvae, and the adult weevils. Practically all of the adult weevils and practically all of the cotton lice are to be found in the growing cotton plants themselves. The greater proportion of the punctured or egg infested squares are also to be foundin the plants and beneath the plants, although a small proportion of these punctured or egg infested squares may also be distributed, over the middle areas of ground'between the plant rows.. Accordingly, it is seen that most effective insect elimination isexercised at or in the plants themselves o1- immediately under the plants. One of the features of the present invention is the provision of improved and squares will have fallen to the ground by sure of approximately 60 lbs. in the air tank give transversely of the row in a rearward position so that the area of flame is distributed over a longer length of plant row, and whereby each point in the plant row-is subjected to flame for a greater length of time.

Another feature of the invention resides in an improved relation of burners for flaming the middle areas between plant rows' and the side areas beyond plant rows.

' Another feature of the invention resides inproviding separate supporting wheels for .the different burners or combinations of burners which are capable of rising and falling relatively to the tractor flame in traveling along the plant rows. Each of these independent supporting wheels is located in immediate proximity to its respective burner and follows the contour of the ground immediately adjacent. that burner so that from the burner nozzles.

the burner is maintained at a substantially con- 'stant height above the ground irrespective of ir-" regularitiesin the ground or any tilting of the 'tractor frame.

Another feature of the invention resides in im-' provements which increase the effectiveness of the time the burner flames reach that particular area of the ground.

Another feature of the invention resides in the provision of improved deflectors which temporarily lift the lower leaves or foliage of long-leaved plants to elevated posi ions so as to hold them up out of the direct paths ofthe flames issuing Such leaf lifting deflectors may be employed advantageously when cultivating tobacco, com and other long leaf plants, particularly at that stage of their growth when the lower leaves hang down in close proximity tothe ground.

Other features, objects, and advantages of the invention will appear from the following detail description of certain preferred embodiments thereof. In the accompanying drawings illustrating suchembodiments:

Figure 1 is a side elevational view, more or less diagrammatic, of a tractor having my improved flame .cultivator apparatus mounted thereon;

Figure 2 is afront elevational view of the cultivator showing the agitating chains at the front of the vehicle for shaking the plants to shake ofl insects, larvae, etc.;

Figure 3 is a front view of the cultivator taken on a plane immediately in rear of the agitating chains, approximately as indicated by the section plane 33- of Figure 1;

Figure 4- is a plan view of the cultivator;

Figure 5 is a rear end view of the same;

v Figure 6 is a longitudinal sectional view, somewhat diagrammatic, through one form of my improvedhigh pressure atomizing burner;

Figure 7 is a fragmentary front elevational view of a modified construction of my invention, this view corresponding approximately to a view taken-on the plane of the line |1 of Figure 8;

Figure 8 is a fragmentary plan view of i this modified construction;

Figure 9 is a fragmentary side elevational view, corresponding-to a vertical section taken approximately on the plane of the line 99 of Figure 8;

Figure 10 is a'detail elevational view of one of the adjustable mounting clamps for mounting the burner units; and

Accordingly, my im- Figure 11 is a view similar to Figure 6; showing a modified construction of burner unit.

Referring first to Figures 1 to 5 inclusive, 1 have shown a tractor 2| of conventional construction suitable for performing ordinary cultivating operations. The tractor comprises a single dirigible wheel 22 or two closely spaced dirigible wheels at the front, and driving wheels 23 at the rear. The front wheel or wheels 22 are steered by a suitable steering mechanism including the steering wheel 24 which rotates a steering spindle in the front post 25 to swivel the wheel 22. The front and rear wheels are connected by a suitable chassis frame 21, and carried by this frame are the internal combustion engine,

clutch, selective speed transmission and drive to the two rear wheels 23. The tractor is prefer- 6 The operating relation is such that the rod 41 can slide upwardly and downwardly within the tubular guide bracket 48, and a compression spring 49 surrounding the lower portion of the rod normally tends to thrust the rod downwardly to hold the supporting wheel 44 against the ground under spring pressure. The upper end of the spring abuts the under side of the tubular guide 48 and the lower end of the spring. abuts an adjustable collar: 5| suitably secured to the arm 41 by a set screw or the like, whereby the collar 5| can be positioned upwardly or down wardly along the bar 41 for increasing or decreasing the effective pressure of the spring 49.

ably provided with an automatic speed governor sufficiently far apart to straddle two plant rows when operating on row crops, these two rows being indicated by the dash and dot lines R and R in Figure 4. The span between such rear wheels is usually adjustable for adapting the implement to the cultivation of crops having difierent row spacing, The front steering wheel 22 runs between the rows R and R.

This type of tractor hasprovision for mounting an implement carrying rock shaft 33 extending crosswise at the front end of the tractor.'

Mounting brackets 34 are detachably secured to the forward portion of thetractor frame 21 and the front ends of these brackets carry suitable journals 35 in which the rock shaft 33 is mounted for. rocking movement. Such rocking movement is utilized to raise and lower the burner units mounted on the rock shaft, this being accomplished through a manually actuated, lever 36 which is accessible to the operator from his position on the tractor seat 29. 36 operates over a latching quadrant 31 and is operatively connected through a link 38 with an arm 39 extending from the rock shaft 33, whereby swinging motion of the manual lever is operative to swing the burner units from a lower operative position to an upper nonoperating position.

There are at least four burner units for the two plantrows R-R', one pair of burner units 4|4| being disposed on the outer sides of said plant rows and another pair of burners 42-42 being disposed on the inner sides of said plant rows. These burners are supported by independent supporting wheels 44 which can rise and fall relatively to the tractor 2| in following the contour of the ground. These four supporting wheels 44 have practically the same operative connection with the rock shaft 33, and, accordingly, a description of one of these supporting wheels and its operative connection will suffice for all. Each wheel is journaled on an axle pin 45 projecting laterally from a bracket 46 which has bolted attachment to the lower end of a spring impelled bar or arm 41. The latter extends upwardly for endwise sliding movement in a tubular guide bracket 48 which is bolted to the rock shaft 33.

through the instrumentality vof an adjustable when these bars and their burner units are swung upwardly to their nonoperating positions. Each burner 4 |-4 and 42-42 has adjustable mountlug on its respective wheel supported bar 41 mounting bracket 54 adapted to be secured by a bolt or bolts 55 to the bar 41. This adjustable mounting enables the burner to be raised and lowered relatively to its individual supporting wheel 44, and also enables the fore and aft and from one burner is set forwardly in advance of the flame of the otherburner so that. the two flames'act in series on the plant row. Thus, in

the arrangement illustrated in Figure 4 thetwo inner burners 42 and 42' are set in advance of The lifting lever rows are first flamed by the inner burners and then flamed by the outer burners. This reduces the intensity of the flame to which each plant is subjected at any instant of time, but increases the time interval over which the plant is subjected to the flames. It will be evident that as the separate supporting wheels pass over undulations in the ground they cause up and down movement of the spring pressed mounting rods 41 and corresponding up and down movements'of the burner units so that the units are always maintained a substantially fixed height above thebase of each plant, irrespective of fore and aft or'lateral inclination of the tractor.

Positioned forwardly of the burners 4 I-42 and 4|'42' are the agitating devices which shake the crop plants for causing insects, larvae and other parasites to drop down to the ground where they will be subjected to the flames from the burners. These agitating devices preferably comlarvae and other parasites on the plants are shaken loose and are caused to drop to the ground under the;plants where they are subjected to the flam ng action of the burners traveling behind the chains. These agitating chainshave paroases ticulariutillty in cultivating cotton plants, where the agitation of the chains has a very beneficial effect in -shaking loose from the plants a goodly proportionof the. boil weevils, punctured or egg infested squares, cotton lice, etc.

of- 'theliquid fuel burners 4I-4I' and 4 2 52. i or the high pressure atomizing type, such as. is diagrammatically illustrated in Figure 6. Each burner comprisesan' atomizing chamber 08 from which extends a burner nozzle 60. The liquid fuel enters the atomizing chamber 05 under pressure through a fuel tube 41 .which terminates in a fuel orifice or nozzle 6 12, Compressed air enters the atomiz ing chamber 65 through an air tube 00 which terminates in an air orifice or nozzle 08. 'Thisair orifice 00 is so positioned with respect to the fuel orifice 61 that the blast of air issuing therefrom exerts a pronounced atomizing effect on the fuel issuing from thefuel orifice." If desired, the capacity of these orifices may be made variable through the substitution of different calibrated orifice plugs, or adjustable metering pins may be provided to vary the area of each orifice. In the preferred arrangement illustrated, I provide a'cock or valve 1i at the upper end of thefuel tube 01, and provide a cock or valve 12' at the upperend of the air tube 08. These valves may be employed for regulating purposes or for shut-off purposes. A rubber tube or other flexible tube 14 establishes-a communication .between the admission'side of eachvalve II and a transversely extending fuel manifold pipe 10. This manifold pipe extends transversely of the tractor adjacent to the rock shaft 33, and supplies fuel to all of the burner units. A similar air manifoldpipe 10 also extends transversely of the tractor adjacentto the-fuel manifold pipe 15. Sections of rubber tubing or other flexible conduit 11 extend'from this air manifold pipe to the admission side of the valve 12' connecting with the air jet tube 08. The provision of the sections'of flexible tubing 14 and 11 accommodate the rise andgfall of the burner units as their supporting wheels pass over.undulations in the ground, and also accommodate the upward swinging movement of the burner units. when the burners andtheir supportin wheels are swung upwardly to their nonoperating positions.

A fuel supply pipe I0 extends rearwardly from the'fuel manifold Jiyand an air supply pipe 10 extends rea'rwardly from the air manifold 16. These two supply pipes connect respectively with a fuel supplyv tank ll and an air supply tank- 02, both of which tanks are preferably mounted in upright relation at the rear of the tractor'to the left and right sides of the tractor seat 29, as best illustrated in Figure 5. The lower ends of the tanksare rigidly clamped in mounting sockets or mounting steps 03 which are suitably secured to the axle'extensions- 84 of the drivehousing 3L,- The fuel supply pipe 18 connects with the 'lowerportion of the fuel tank 8| through a valve which is readily accessible to the operator sation and enables it to be readily drained from the system. The air supply pipe 10connects' with any desired point of the air storage tank 02, preferably adlacent to the upper end thereof as shown in Figure 5. A relief valve 89 opens from the bottom of the air reservoir 02, this valve also serving to drain any condensate from the bottom of the reservoir 02.

The ,air compressor II is preferably a four cylinder, 'V-type of compressor-which is shown as being mounted under the driver's seat 20. A

I power take-off shaft 92 projects from the rear end of the drive housing II, and is operatively coupled with the air compressor 0i. In the preferred arrangement illustrated, the drive is effected by mounting a sprocket wheel 03 on the power take-off shaft and by mounting a similar sprocket wheel 04 on the compressor shaft, and connecting these two sprocket wheels with the drive chain -90. A protecting housing 06 encloses the sprock- .et wheels and drive chain. The power take-oil shaft 92 can be connected to and disconnected from theengine of the tractor at any time, as is well known in these cultivating types of tractors. An air filter 80 is secured to the chain housing cover 80 and supplies cleaned air through the intake manifolds 09 to the four cylinders of the compressor. The outlet manifold IIII leading from the compressor cylinders conducts the compressed air through an after-cooler I02 which serves to reduce the temperature of the compressed air before entering the air reservoir 02. A check valve I08 is interposed in the pipe connection I04 leading from the after-cooler to the air tank 02. A pressure transmitting pipe I00 extends across from the top of the air tank 02 V to the top of the fuel tank 8|.

is connected to the pressure transmission pipe I00 on the airtank side of the valve I01, whereby this gauge I08 always indicates the pressure existing in the air tank 82. Similarly, another pressure gauge I09 is connected to the pressure transmitting pipe I0l-on the fuel tank side of the pressure regulating valve, I01 for indicating the pressure prevailing in the fuel tank IL A pressure relief valve III may also be connected with the fuel tank 8| so as to prevent possibility of an abnormally high pressure arising in the tank II.

The liquid fuel is introduced into the tank BI through a suitable fuel inlet ll2 having a shutoff valve Ili.

It will be seen from the foregoingthat the operator can run the compressor 9| for longer or shorter intervals and thereby increase or decrease the pressures prevailing in the tanks II and 82 over a wide range of adjustment. -It will also be seen that the operator can establish and maintain any desired pressure differential between the tanks BI and 02 by opening and closing the valve I01. By the performance of these regulating operations, and theperformance of the other regulating and adjusting operations previously described, the operator can readily vary the intensity, of the burner flames through a considerable range, and can also vary the length of the burner flames through a substantial range. Under average operating conditions, I find that it is desirable to maintain a pressure of approximately lbs."per square inch in the air tank 42, and a pressure of appronmately 40 pressure prevailing in the fuel tank 8 l 9 lbs. per square inch in the fuel tank 3L. These pressures give very satisfactory performance when using distillate and other comparable fuel oils. It will be apparent that if it is desired to increase the intensity of the burner flame this can be done by raising the pressure effective on the fuel in the tank 3| for causing an increased proportion of fuel to flow to the burner, and, conversely, when it is desired to reduce the intensity of the flame this 'can be done by reducing the Furthermore, if it is desired to increase or decrease the length of the flame projected from each burner unit, this can be brought about by increasing or decreasing the two pressures prevailing in the compressed air tank 82 and the .fuel tank Bl, the higher pressures resulting in a longer flame and the lower pressures in a shorter flame. It will thus be seen that the operator can adjust the intensity of the flame and the length of flame to meet all crop conditions, ranging from a low intensity flaming for young crops, to a high intensity flaming for mature 'crops having relatively thick stalks,and also ranging from a relatively short flam for young crops to a relatively long flame for reaching in under-mature crops having long leaves or long upper foliage. Under all of these variable operating conditions, the burner flame is maintained in a relatively fixedrelation to the bases of the crop plants by reason of the mounting of the burner units on the separate supporting wheels 44. When the tractor is being run to and from the field, the burner units and plants.

" from a hub I29 which is mounted on the rock supporting wheels 44 can be swung up to inopsired, be utilized to incline the spring pressed rods 41 forwardly or rearwardly to a greater or lesser angle to insure free rise and fall of the spring pressed rods in the travel of the wheels 44 over irregularities in the ground level.

Referring now to the modified construction illustrated in Figures '7 to 11 inclusive, this modifled embodiment differs from the preceding embodiment principally in the feature of having the independent wheel supports for the burner units pivotally mounted so as to be capable of an up and down swinging movement instead of an endwise sliding movement when passing over irregular ground; also,- in the feature of having the burner units project a fan shaped or flshtail flame; and, furthermore, in the feature or providing leaf lifting devices for lifting the lower leaves orfoilage of the crop plants up out of the direct path of the flames issuing from the burner nozzles. The construction of the tractor 2i and the arrangement of the various parts thereon is substantially the same in the case of this modifled embodiment, and hence thedescription of that portion of the disclosure need not be repeated. The bracket arms 34 extending forward ly from the tractor carry the transverse rock shaft 33, and extensions 34 of these bracket arms project forwardly for mounting the rod 62 and chains GI, substantially as heretofore described. Each independent supporting wheel 44 is journaled on the lower end of a supporting arm I2I which has its upper end journaled for free swinging movement'about the rock shaft 33. As best shown in Figure '7, each arm I2I has its upper end secured in the lower portion of, a mounting yoke I22, the arms of which are formed with split bearings I23 adapted to be mounted over bearing bushings I24. The bushings have wide outer grooves formed therein, and the split bear- .ing bosses I23 are assembled inthese grooves for rotation therein. Stop collars I26 are secured to the rock shaft 33 by set screws I21 or the like for determining the lateral position of each yoke I22 along the rock shaft 33. be understood that by loosening the set screws I21 in the stop collars I26 the entire yoke and.

arm assembly can be shifted transversely to differentpositions along the' rock shaft 33 if it should be desired to adjust the lateral position of one or more burner units to accommodate different row spacing of the crop plants or to dispose the burners closer to or further from the A lifting arm I28 extends downwardly shaft 33 between the arms of the yoke I22. The hub I23 is free to slide endwise along the shaft 33 in the performance of any shifting adjustments of the yoke alongv the shaft, but said hub and lifting arm are compelled'to rock directly with the shaft 33, such result being obtained either by forming the rockshaft of polygonal cross section or by providing'a sliding key or spline arrangement between the rock shaft and the hub I29. As shown in Figure 9, the lifting arm I28 normally occupies 9, position spaced rearwardly from the yoke I22 and arm I2I, so that the arm I 2| is free to'swing up and down with the wheel 44 as the latter passes over uneven ground. However, when the operator desires to described for rocking the rock shaft 33 in a counterclockwise direction. This swings the lifting arms I28 forwardly for positively raising all of the wheel supported arms I2I upwardly to their nonoperating positions. Each of these wheel supported arms I2I is preferably of cylindrical tubular cross section, and has its lower end curved forwardly and bent laterally .to form a journal on which the ground wheel 44 is mounted. These arms I2I are'shown as being inclined"ina;for ward direction in order to dispose the burner units 4I-4I' and 42--42' considerably in ad- Vance of the pneumatic tire on theiront tractor wheel 22, but my invention also contemplates an alternative arrangement wherein thelfarms I2I are inclined downwardly in a, reaiward direction from the axis of the rock shat? particularly where this rock shaft is'dispdsed further forward, or where the entire front tr "1' wheel 22 is of such construction, or i's'l' gshielded in such manner, that the heat 0 burner flames will not injure this wheel. each supporting wheel 44 asses over irregularit es in the ground it swings its own supporting arm I2I upwardly or downwardly entirely independently of the supporting arms I2I in 'suchmanner. that the burner can be adjustedvertically to different heights along the straight portion'of the arm, and can also be swiveled horizontally to different angular positions around the axis of this arm. Figure 10 illustrate a typical clamping type'of mounting which enables the burner unit to have these adjustments relatively to said arm. The

clamp or mounting bracket is designated I30 in its entirety, and comprises a first clamping section l3l which clamps around the arm I2-l, and

It will a second clamping section 132 which clamps around the burner unit. The section ill is off split formation formed with ears ll! projecting forwardly from each semicircular half and adapted to receive clamping bolts IN. This arrangement enables the section Hi to be slid up cases tion for average working conditions and average mg chamber 65 of the burner unit, and enables the burner unit to be shifted forwardly or backwardLv in the clamping section, or 'to be rotated axially about the center of the clamping section to dispose the fan-shaped burner nozzle a at different angles. Projecting from the first clamping section I! I, at an angle thereto, is a substantially circular clamping boss I31, and projecting from the second clamping section III, at an angle thereto, is a companion boss III. These two bosses are formed with circularly formed clamping faces provided with radially extending serrations l3l' and I3!" respectively which are clamped in matching relation by a clamping bolt I39 passing through the two bosses. Releasing this bolt enables the second clamping section I32 to be swiveled upwardly or downwardly around the axis of the bolt I39, thereby enabling the vertical angle of the burner unit to be turned upwardlyor downwardly for directing the burner flame more obliquely or less obliquely to the surface of the ground.

This modified embodiment illustrates the preferred construction of burner unit wherein the nozzle is of fan-shaped or flshtafl outline, as indicated at a. This form of nozzle is advantageous for the purpose of producing a flame which is of;considerable width horizontally for covering a large area of ground. but which is of relatively shallow depth vertically so as to minimize injury to the lower leaves and lower foliage extending outwardly from the crop plants. Figure 11 illustrates the slightly modified form of atomizing chamber 65a which may be embodied in any of these burner units. In this modified construction, the liquid fuel enters the upper rear portion of the atomizing chamber through fuel tube 61a terminating in fuel orifice 61", and the compressed air enters the upper portion of the atomizlng chamber through air tube 68a terminating in air jet 68'. The rear end of the atomizing chamber is formed with an oblique deflecting surface 0. The air orifice 68' discharges across the end of the fuel orifice 61' and impinges at an angle on the deflecting surface H0. The construction and arrangement is such that the stream of air issuing from the air orifice exerts -a pronounced I atomizing effect on the stream of fuel issuing fromthe fuel orifice at right angles thereto, this mixture of air and fuel then striking the deflecting surface I40 and being deflected at a downward inclination through the fan-shaped nozzle 68a. The impingement of the air and the fuel particles againstthe inclined deflecting surface H0 causes the fuel particles to be subjected to further atomization, and, in addition, the striking of the stream of air and fuel against such surface tends to fan the stream outwardly in sidewise relation to aid in forming the flshtail-shape of flame issuing from the nozzle "a. While the modified construction of burner illustrated in Figure 11 is the preferred construc t p s of plants may make it advisabieto employ the circular type oi' burner nomle I. in conJunc-- .'tion with the deflecting type of atomizing chamber Ila, or to employ the fan-shaped nozzle is in conjunction with thestraight atomizlng chamber ll, if desired.

Referring to Figure 8, I have shown the same previously described arrangement of outer and inner burners II and I! for the right hand plant row R, and outer and inner burners ll and 12 for the left hand plant row R. The inner and outer burners of each pair are likewise arranged in staggered or oiiset relation, preferably with the inner burners 42, 42' disposed forwardly of the outer burners 4|, 4|, althoughthis arrangement may be reversed if desired. The degree of oiiset between the burners is preferablysuch that the rear edge of the fan-shaped flame of the front burner approximately coincides with the forward edge of the fan-shaped flame of the rear burner. This results in the burners covering a maximum expanse of horizontal area along the crop row, with a minimum vertical depth of flame. Figure '1 illustrates the preferred setting of the burners for average crop and soil conditions, with the burner flames striking the ground short ofthe plant and then fanning out beyond the plant or around it.

The modified embodiment shown in Figures '7 to 11 inclusive, also illustrates the provision of additional burners arranged to flame the middle areas between the plant rows. These middle areas will be flamed to some extent by the transversely extending burners ll-ll', 42-42, but the middle areas maybe flamed more intensively by providing additional burners devoted primariLy to those areas. Such additional burners are typically illustrated at llllli' and 2- 2' in Figures 7 and 8. These latter burners can be identical in all respects with the transversely extending burners, the only difference being of the angle of mounting on their respective wheel supported arms III; This angle is in a more or less forward direction, with the fan-- sites which may be lying on the ground in these middle areas.

In this modified embodiment illustrated in Figures 7 to 11 inclusive, I have also shown leaf lifting devices for raising the lower leaves of long leaved plants so as to get these leaves up out of the direct path of the flames issuing from the burners. An outer leaf lifter III follows along the outer side of each plant row, and an inner leaf lifter I52 foliowsalong the inner side of each plant row. As shown in plan in Figure 8, the forward ends of these leaf lifters curve awayfrom' the line of the plant row, as indicatedvat l5l' and I52. These curved forward ends form deflecting surfaces or sloping'guide surfaces for deflecting the plants and their lower leaves into the passa eway between the straight rear ends of the leaf lifters. Viewed in side elevation, as shown in Figure 9, the forward end of each leaf lifter travels in relatively close proximity to the ground, being maintained at a spaced distance from the ground by the associated supporting wheel 44. From 13 this front end the leaf lifter slopes upwardly to raise the lower leaves of the plant to a plane above the flames projected transversely by the staggered burners lL-fl, I -42'. The rear end of the lifter can slope downwardly, if desired, at a point beyond the transverse plane of its associated burner. Each leaf litter may be arranged for independent mounting on the adjacent wheel supported "arm |2l through the medium of an adjustable mounting bracket, if desired, but a more simplified arrangement is, to mount each leaf lifter on its associated burner unit. This can be readily accomplished by riveting or welding bars I" to the nozzle "a of each transverse burner, and having these barsextend outwardly and upwardly for attachment to the leaf lifter at points approximately in prolongation of the burner nozzle. This mounting will insure that each leaf lifter will remain in a predetermined relation to its respective burner unit in any adjustment of the burner unit. As shown in Figures 1 and 8, the two leaf lifters at each side of each crop plant move in under the long lower leaves and lower foliage of the plant and gradually deflect these leaves and foliage upwardly so that the transverse burners can project their flames against the bases of the plants and over the adjacent ground without having these lower leaves and lower foliage in the direct path of the flames where they might be deleteriously burned by the flames. It will also be noted that the two leaf lifters HI and I52 cooperate to form a guiding throat for straightening up plants which may be leaning to one side. and for deflecting plants which are substantially out of line in the plant row back to a position more nearly in line, whereby to properly position all of the plants for the most eilective action of the burner flames on the bases of the plants and the surrounding ground areas. These leaf lifters are of particular advantage in connection with tobacco, corn and other long leaved plants, but need not be employed in. connection with these crops or other crops when the leaves are short and do not get into the path of the burner flames.

My improved cultivator can also be used on pineapple plantations and in other situations where paper is used to control weed growth. Tests have proven that celery paper will not'be i nited by the bumer flames. Other papers may require that the burner flames be reduced in intensity. but the wide range of adjustment which can be obtained by my improved regulating apparatus makes this entirely practicable. The wide range of regulation of the intensity and size of the burner flames can also be utilized to compensate for wind conditions. The speed of the tractor can be widely adjusted by variation of the governor setting, and by the selection of different speed ratios in the transmission, so as to increase or decrease the length oftime that each crop plantis subjected to the action of the flame. For example, with a typical tractor having a three-speed or four-speed transmission, a variety of speeds ranging from /2 mile per hour to 4 aaaoa hills immediately after planting and before the plants have come up.

While I have illustrated and described what I regard to be the preferred embodiments of my in- I vention. nevertheless it will be understood that suchare merely exemplary and that numerous modifications and rearrangements may be made therein without departing from the essence of the invention.

\ air under pressures .of approximately 60 pounds per square inch, a plurality of high pressure atomizing burners propelled by said vehicle and having a fuel nozzle connected to receive liquid fuel under pressure from said fuel supply means and having an air nozzle connected to receive compressed air from said air supply means, said air nozzle exerting an atomizing action on the fuel from the fuel nozzle in each burner and also creating a long flame, said burners being arranged to project relatively long flames upon the ground on opposite sides of the plant row and directed generally crosswise of the plant row whereby said long flames pass through and beyond the plant row for destroying weeds directly in the'plant row, and regulating means cooperating with one of said supply means for controlling the intensity of flame or length of flame projected from each burner.

2. In a cultivator adapted to cultivate row 'crops by the flame method, the combination of a tractor having a front wheel traveling between adjacent rows and rear wheels spanning adjacent hows, a fuel reservoir on said tractor, a comor 5 miles per hour can be had for a wide variety tions, to all of which my improved implement can 'be adapted. Under certain operating conditions it may be desirable to flame the plant rows or pressed air reservoir on said tractor, means driven by the tractor engine for maintaining pressures in both of said reservoirs, a plurality of high pressure atomizing burners connected with the forwardportion of the tractor and receiving fuel and air under pressure from said reservoir, said burners being arranged to project relatively long flames upon the ground on opposite sides of adjacent plant rows straddled by the tractor and directed generally toward the plants in the two plant rows, and regulating means cooperatingand means carried by said vehicle for supplying i liquid fuel and air, to separate fuel and air nozzles in said burners under pressures of approximately 40 pounds for the fuel and 60 pounds for the air whereby to atomize the liquid fuel at each burner and to cause each burner to project a relatively long flame which is directed substantially crosswise of the plant row to pass through and beyond the plan row at a level below the lower leaves of the crop plants for flaming the ground immediately around the bases of the crop plants without injuring the upper foliage of the plant.

4. In a cultivator adapted to cultivate row crops 'aaeoa respect to the plant row projecting a long flame crosswise of the plant row whereby said long flame passes through and beyond the plant row to act on weeds in the row in the travel of said vehicle, means on said wheeled vehicle for supplying fuel to said burner, and a wheeled support for said burner coupled to said wheeled vehicle whereby said burner is propelled by said vehicle but can rise and fall relatively thereto, in the travel of its wheeled support over the ground.

' 5. In a cultivator adapted to cultivate row crops by the flame method, the combination of a tractor having a front wheel traveling between arflacent rows and rear wheels'spanning adjacent rows, a plurality of burners positioned between said adjacent rows and on the outer sides of said adjacent rows and projecting flames upon the round or adjacent to the bases of the plants in said rows, means on said tractor for supplying fuel to said burners, separate supporting wheels breach of said burners, and means coupling said separate supporting wheels with said tractor whereby each burner andits separate supporting wheel can rise and fall relatively to said tractor and to the other burners in the travel of the cultivator over uneven ground.

6. In apparatus of the class described, the

combination of a wheeled vehicle, a burner propolled by said vehicle adapted to project a flame in predetermined relation to the crop in the travel of said vehicle, means on the vehicle for supplying fuel to said burner, and a separate wheeled support for said burner comprising an arm having endwise slidable connection with saidwheeled vehicle, a separate supporting wheel at the lower end of said arm, and spring means acting on said arm normally thrusting said separate supporting wheel against the ground.

7. In apparatus of the class described, the combination of a. wheeled vehicle, a plurality of burners propelled byfsaid vehicle adapted to project flames in predetermined relation to the" crop in the travel of the vehicle, means on the vehicle for supplying fuel to said burners, and separate wheeled supports for said burners each compris ing an arm pivotally mounted on said wheeled vehicle for up and down swinging, movement, and a ground .wheel ,at .the lower end of each arm .capable of rising and falling relatively to the rows, and a pair of burners propelled by said vehicle and adapted to project flames substantially crosswise of the row in the travel of the vehicle along the row, said burners being in staggered relation whereby the flame from one burner acts on the plants or ground area of the row in advance of the flame from the other burner.

,9. In a cultivator adapted to cultivate row crops by the flame method, the combination of a tractor having a front wheel traveling between adjacent rows and rear wheels straddling adjacent rows, apair of outer burners on said tractor positioned to travel along the outer sides of said adjacent rows, and a pair of inner burners on said tractor positioned to travel along the inner sides of said adJacent rows, said burners I projecting their flames substantiallyv crosswise of said rows and the burners acting on each row being oilset with respect to each other whereby their flames act in series on the plants in each row.

by the flame method, the combination of a wheeled vehicle, and a burner propelled by said vehicle and operative to project a flame in predetermined relation to the crop, said burner be-.

ing constructed and arranged to project a flame of relatively wide horizontal dimension so as to cover a considerable area of ground, and of rela- 'tively small vertical dimension so as to minimize the likelihood of injuriously burning th upper zontal dimension and of relatively small vertical dimension. I h I 12. In a cultivator adapted to cultivate row crops by the flame method, the combination ofa wheeled vehicle, a burner propelled by the vehicle projecting a relatively long unobstructed flame substantially crosswise of the plant row and entirely through and beyond the plant row for direct impingement against weeds in the plant row, and means carried by said vehicle for lifting the lower leaves of the crop plants substantially out of the path of said flame during the cultivating operation.

13. In a cultivator adapted to cultivate row crops by the flame method, the combination of a tractor having a front wheel traveling between adjacent rows and rear wheels spanning adjacent rows, a plurality of fluid fuel burners propelled by said tractor and disposed at the outer and inner sides of said adjacent rows for projecting flames aroundthe bases of the crop plants in said rows, and leaf lifting deflectors carried by said tractor on the outer and inner sides of said plant rows for lifting the lower leaves of the crop and other parasites to fall from the plants down to the ground, and a burner propelled by the vehicle operative to thereafter project a. relatively long unobstructed flame substantially crosswise of the plant row to pass through the plant row for imping'ement against the ground directly under the plants to destroy such insects and other parasites.

.15. The method of destroying or inhibiting in sects and other parasites in row crop plants,,

which comprises shaking the crop" plants so as to cause the insects and other parasites to fall from the plants down upon the ground, projectand beyond said row whereby said-long flame impinges directly against the ground substantially under the plants to destroy or inhibit insects or other parasites on the ground under the plants,

10. In an implement adapted to cultivate crops to the crop plants.

and moving the flame along the row at a rate which; will destroy or inhibit such insects or other parasites without causing substantial in- J ry to the crop plants. l

16. In a cultivator adapted to cultivate row crops by the flame method. the combination of a tractor having a front wheel traveling between adjacent rows and rear wheels straddling adjaand positionedto project flames along the middle areas between said rows.

17. In a cultivator adapted to. cultivate row crops by the flame method, the combination of a tractor having a front wheel traveling between adjacent rows and rear wheels straddling adjacent rows, a plurality of burner propelled by the tractor and adapted to project flames from the inner and outer sides of said plant rows around the bases of the plants in said rows. and adjustable mounting clamps connecting said burners with said tractor whereby said burners can be inclined to different vertical angles. and can be swiveled to different horizontal angles.

. 18. In a cultivator adapted-to cultivate row crops by the flamemethod, the combination of a tractor having a front wheel traveling between said conduit means interconnecting said air and e "ea-dos I8 ing apparatus for governing the action of said burners comprising adjustable valve means in fuel reservoirs for'establishing a pressure dinerential between said reservoirs, and adjustable valve/means in said conduit means interconnecting said fuel reservoir'and said fuel jet for varying the rate of flow of fuel to said burners.

'21. In an implement of the class described the combination of, a wheeled vehicle, a plurality of burners carried thereby adapted to project flames in predetermined relation to a growing crop,

means on said vehicle for supplying fuel to said burners, supporting arms for said burners, and adjustable mounting clamps for adjustably mounting said burners on said supporting arms.

each of said mounting clamps comprising a flrst' clamp section embracing a supporting arm and shiftable to different vertical positions and to different angular positions relatively to said arm. a second clamp section embracing the burner and enabling the latter to be rotated to different angular positions in said clamp section, and means adjustably coupling said clamp sections together adjacent. rowsand rear wheels straddling adjacent rows, a. plurality of burners propelled by the tractor and positioned on the outer and inner across the front portion of said tractor, means sides of said adjacent rows for projecting flames around the bases of the plants in said rows, and

' means mounting said burners on said tractor enabling said burners to be adjusted transversely of the tractor to accommodate different row spacing of different crops.

19. The method of treating a standing row of stemmed crop plants to suppress insect life on the plants which comprises agitating the plants to cause the insects to drop therefrom to the ground beneath the plants, directing relatively .long unconfined blasts of hot fluid from each side of the standing rowLsubstantially crosswise of the row to pass through and beyond the standing row, said blasts bathing the insects, the vegetation, and the stems of the standing crop plants in the .hot fluid, and moving the blasts.

of hot fluid along the row at a rate which will continue the application of heat long enough to injure the insect life without substantial injury 20. In an implement adapted bination of a tractor, an air compressor driven by the engine of said tractor, an air reservoir and and also causing said burner to project a relativeto remove weeds from plant rows by the flame method, the comin diflerent angular positions, whereby to pro-v vide a wide range of adjustment of the burner.

22. In a cultivator adapted to cultivate row crops by the. flame method, the combination of a tractorhaving a front wheel travelin between adjacent rows and rear wheels straddling, adjacent rows, a rock shaft extending transversely operative to rock said rock shaft, and burners carried by said rock shaft and disposed on the inner and'outer sides of said adjacent rows to project flames ,on the bases of the plants in said rows, the rocking of said rock shaft being operativeto swing said burners upwardly to non-operatingpositions.

23. In a cultivator adapted to cultivate row crops by the flame method, the combination of a tractor having a front wheel traveling between adjacent rows and rear wheels straddling said a jacent rows, a plurality of burners on said tractor disposed on the outer and inner sides of said adjacent rows and projecting flames on the bases of the plants in said rows, a fuel reservoir on said tractor supplying fuel to said burners, a compressed air reservoir on said tractor supplying compressed air to said burners, and a compressor driven 'by said tractor for supplying pressure to said reservoirs.

- 24. In a cultivator adapted to cultivate row crops by the flame method, the combination of a wheeled'vehiole, a burner disposed to project a relatively long flame substantially .crosswise of the plant row to pass through the row, whereby said flame is caused to impinge directly against weeds in the plant row in the travel of said vehicle, means on said wheeled vehicle for supplying fuel to said burner, and a ground engaging support for said burner coupled to said ly'long flame, said burner being disposed to project said long flam substantially'unobstructed in a direction crosswise of the plant row to pass through and beyond the plant row for impinging against weeds in the row in the travel of the wheeled vehicle whereby said burneris propelled by said vehicle but can rise and fall relatively; thereto in the travel of its ground engaging support over the ground.

25. In a cultivator adapted ,to cultivate row crops by the flame method, the combination of a wheeled vehicle adaptedto travel along the plant rows, a plurality of. burners propelled by said vehicle projecting relatively wide fan-shaped flames substantially crosswise of the plant rows,

means on said vehicle for supplying fuel to s'aid burners, separate ground engaging. supports for said burners, and means pivotally coup i said l9 separate ground engaging supports with said wheeled vehicle'whereby each burner and its separate ground engaging support can rise and fall relatively to said wheeled vehicle and to the other burner in the travel of the ground engaging supports over uneven ground.

26. In a cultivator adapted to cultivate row crops by the flame method, the combination of a wheeled vehicle adapted to span one or more plant rows, a plurality of burners propelled by said vehicle projecting relatively wide fan-shaped flames substantially crosswise of said 'plant rows from opposite sides of the row for passing through the. row,. means on said vehicle for supplying fuel to said burners, an individual ground engaging support for each of said burners, adjustable clamp means interconnecting each burner and its individual ground engaging support so as to enable the burner to be adjusted relatively to its support, means individual to each ground engaging support for movably coupling the same with said wheeled vehicle whereby each burner and its'individual ground engaging support can rise and fall relatively to said wheeled vehicle and to the other burners in the travel of the ground engaging supports over uneven ground, and lifting means actuatable by the operator from his driving position on said wheeled vehicle while the latter is i'nmotion for lifting all of said burners to non-operating positions.

27. In a cultivator adapted to cultivate row crops by the flame method, the combination of a'wheeied vehicle adapted to travel along the rows, a plurality of burners propelled by said vehicle projecting flames'around the bases of the plants in the plant rows, free floating ground engaging supports for said burners, and adjustable means connecting said ground engaging supports with said vehicle enabling said ground engaging supports and burners to be shifted transversely relatively to each other to diflerent P tions crosswise of said vehicle.

28. In a .cultivator adapted to cultivate row '-crops by the flamemethod, the combination of a wheeled vehicle adapted to travel along adjacent r'ows, a plurality of burners propelled bysaid ve-' hicie positioned between said adjacent rows and on the outer sides of said adjacent rows and projecting flames substantially crosswise of said rows,

and burners propelled by said vehicle and positioned to project flames along the middle areas between said rows.

- 29. In a cultivator adapted'to cultivate row crops by theflame method, the combination of a wheeled vehicle adapted to travel along adjacent rows, a plurality of burners propelled by said vehicle and adapted to project flames from the inner and outer-sides of said plant rows around the bases of the plants in said rows, and

adjustable mounting clamps connecting said burners with said vehicle whereby said burners be-inclined to difl'erent vertical angles and can be swiveled to different horizontal angles.

30. In, a. cultivator adapted to cultivate row crops by the flame method, the combination of a wheeled vehicle adapted to travel along adjacent rows, a. plurality of burners propelled by said vehicle and positioned on the'outer and inner sides of said adjacent rows for projecting flames around the bases of the plants in said rows, and means mounting said burners on said vehicle enabling said burnersto be adjusted transversely of the vehicle to accommodate different row spacing of diiferent crops.

31. In a cultivator adapted to cultivate row wheeled vehicle adapted to travel along adjacent rows, a rock shaft extending transversely of said wheeled'vehicle, means operative to rock said rock shaft, and burners carried by said rock shaft and disposed along the sides of said adjacent rows to project flames on the bases of the plants in said rows, the rocking of said rock shaft being operative to swing said burners upwardly to nonoperating position.

32. In a cultivator adapted to cultivate row crops by the flame method, the combination of a tractor adapted to travel along adjacent plant rows, a plurality of burners onsaid tractor disposed along the sides of said adjacent rows and projecting flames on the bases of the plants in said rows, 9. fuel reservoir on said tractor sup-l.

plying fuel to said burners, a compressed air reservoir on said tractor supp ying compressed air to said burners, and a compressor driven by said tractor for supplying pressure to said reservoirs.

33. In a cultivator adapted to cultivate row crops by the flame method, the combination for mounting on a wheeledvehicle of a burner disposed angularly with respect to the plant row,,

fuel supply means connected to said burner, said burner and fuel supply means cooperating to cause said burner to project a relatively .long

flame crosswise of the plant row whereby said long flame passes through and beyond the plant row to act 'on weeds in the row, and a ground engaging support for carrying said burner and disposed to be movably connected-to said vehicle whereby said burner when propelled by said vehicle can rise and fall relatively thereto in the 7 travel of its support over the ground.

34. In a cultivator adapted to cultivate row crops by the flame method, the combination for mounting on a wheeled vehicle adapted to travel along the plant rows of a pair of burners, a support. member for each burner adapted to be'mov ably attached to said vehicle and to carry said burners in staggered relation, fuel supply means connected to said burners, said burners and fuel supply means cooperating to cause said burners to project relatively long flames substantially crosswise of a plant row whereby said long flames pass through and beyond the plant row and act on weeds in the row and the flame from one burner acts on the plants or ground area of the row in advance ofthe flame from the other bumer, and a ground engaging support for each support member whereby said burners when propelled by said vehicle can individually rise and crop, said burner having a fan shaped nozzle to fall relatively thereto in the travel of their ground engaging supports over the ground.

35. In an implement adapted to cultivate crops by the flame method, the combination for mounting on a wheeled vehicle, of a burner operative to project a flame in predetermined relation to the project a flame of relatively wide horizontal ,dimension so as to cover a. considerable area of ground, and of relatively small vertical dimension so as to minimize the likelihood of injuriously burning the upper foliage of the crop. a support disposed to be connected to said vehicle for carrying said burner in the aforesaid relation to the crop, and fuel supply means connected to said burners for supplying fuel thereto to maintain said flame. 1

36. In a. cultivator adapted to cultivate row crops by the flame method, the combination for mounting on a wheeled vehicle of a burner disposed angularly with respect to the plant row,

crops y the flame method, the .combination of a cause said burner to project a relatively long I aasos flame crosswise of the plant row whereby said long flame passes through and beyond the plant row toacton weeds in the row, a support adapted to be connected tov said vehicle for carrying said burner, and means also adapted to be carried by.

said vehicle and to be moved thereby immediately ahead of said burner for lifting the lower leaves of the crop plants substantially out of the path of said flame during the cultivating operation.

37. In apparatus of the class described, the combination for mounting on a wheeled vehicle adapted to travel along plant rows of means adapted to be carried-by the forwardpart of said vehicle for shaking the plants to cause insects and other parasites to fall from the plants down to the ground, a burner adapted to be carried by said vehicle'behind said plant shaking means, and fuel supply means connected to said burner, said burner and fuel supply means cooperating to cause said burner to project a relatively long flame crosswise of the plant row to pass through the plant row for impingement against the ground directly under the plants to destroy such insects and other parasites and to act on weeds in the plant row.

38. In an implement of the class described, the combination for mounting on a wheeled vehicle of a plurality of burners adapted to project flames" in predetermined relation to a growing crop, fuel supply means connected to said burnersfor supplying fuel thereto, supporting arms for said burners, and adjustable. mounting clamps for adjustably mounting said burners on said supporting arms, each of said mounting clamps comprising a first clamp section embracing a supporting arm and shiftable to different vertical positions and to different angular positions relatively m to said arm, a second clamp section embracing the burner and enabling th latter to be rotated to different angular positions in said clamp section, and means adjustably coupling said clamp sectionstogether in diiferent angular positions, whereby to provide a wide range of adjustment of the burner. v

39. In a cultivator adapted to cultivate row crops by the flame method, the combination for mounting on a wheeled vehicle of a burner disposed angularly with'respect to the plantrow, fuel supply means connected to said burner, said burner and fuel supply means cooperating to cause said burner to project a relatively long flame crosswise of the plant row whereby said long flame passes through and beyond the plant row to act on weeds in the row, and a ground engaging support for carrying said burner and disposed to be rockably connected to said vehicle whereby said burner when propelled by said vehicle can rise and fall relatively thereto in the travel of its support over the ground.

40. In a cultivator adapted to cultivate row crops by the flame method, the combination for mounting on a wheeled vehicle adapted to travel along the rows, of a plurality of burners projecting flames around the bases of the plants in the plant rows, ground engaging supports for said burners adapted to be connected to said vehicle in a free floating manner whereby said burners are propelled by said vehicle but can rise and fall relatively thereto in the travel of their individual ground engaging supports over the ground, and adjustable means enabling saidground engaging supports and burners to be shifted transversely relatively to each other to different positions crosswise of said vehicle. i

.41. In a cultivator adapted to cultivate row cropsvby the flame method, the combination for mounting ona wheeled vehicle adapted -to travelalong adjacent rows of a first set of burners v positioned between said adjacent rows widen the outer sides of said adjacent rows'for projecting flames substantially crosswise of said'rows, sup-v port means 'adapted to be connected to said vehicle for carrying said first set of burners, a second set of burners positioned to project flames along the area between said adjacent rows, and support means also adapted to be connected to said vehicle for carrying said second set of burners.

'42. In a cultivator adapted to cultivate row .crops by the flame method, the combination for mounting'on a wheeled "vehicle adapted to travel along adjacent rows, of a plurality of burners, fuel supply means connected to said burners, said burners and fuel supply means cooperating to cause said burners to project flames from the inner and outer sides of said plant rows around the bases of the plants in said rows, 9. support member for each burner adapted to be carried by said vehicle, and adjustable clamps for mounting said burners on said support members whereby with respect to the ground said burners can be inclined to different vertical angles and can be swiveled to different horizontalangles.

43. In a cultivator adapted to cultivate row crops by the flame method, the combination for mounting on a wheeled vehicle adapted to travel along adjacent rows, of a plurality of burners positioned on the, outer and inner sides of each of said adjacent rows, support means adapted to 44. In a cultivator adapted to cultivate row I crops by the flame method, the combination for mounting on a wheeled vehicle adapted to travel along adjacent rows of a transversely extending rock shaft, means operatively connected to said rock shaft for rocking the same, and burners carried by said rock shaft and disposed along the opposite sides of each of said adjacent rows to project flames on the bases of the plants in said rows crosswise thereof, the rocking of said rock shaft being'operative to swing said burners upwardly to nonoperating position.

45. In a cultivator adapted to cultivate row crops by the flame method, the combination for mounting on a wheeled vehicle adapted to travel along the rows, of a plurality of burners projecting flames around the bases of the plants in the plant rows, and ground engaging supports for said burners adapted to be connected to said vehicle in a free floating manner whereby said burners are propelled by said vehicle but can rise and fall relatively thereto in the travel of their individual ground engaging supports over the ground.

46. Means attachable to a vehicle adapted to travel along plant rows for cultivating the same by the flame method comprising an attachment aaeoa' 23 a ground engaging element at the lower end of said swinging arm, and a burner carried by said am crosswise thereof near said lower end.

47.11am attachable to a vehicle adapted to travel along plant rows for cultivating the same.

by the flame method comprising an attachment for connection to the vehicle, a ground engaging member swingingly connected to said attachment whereby the movement thereoi' partake; of the movement of the vehicle and ot the rise and tall" 0! the ground engaging as the contour of the ground varies, and a urner carried by'saidground engaging member crosswise thereof adjacent said ground engaging part so that the movement of the burner corresponds closely to variations in the contour of the ground.

PRICE c. McLEMORE. 

